Gene mutation shown to cause leukaemia and lymphoedema

Researchers have discovered a gene that when mutated can cause lymphoedema (swollen limbs due to a failure of the lymph system), immune abnormalities, deafness and leukaemia. The identification of the gene responsible for causing this rare combination of medical conditions, known as Emberger syndrome, could allow earlier identification and treatment of those at risk.

This study, which is published online in the journal Nature Genetics this week (Sunday 4 September), showed that it is caused by a mutation in the GATA2 gene.

Mutations in this gene have very recently been associated with the development of leukaemia and immunodeficiency but had not previously been linked to lymphoedema.

The study was led by a team at St George’s, University of London and St George’s Hospital. The researchers recruited eight patients with Emberger syndrome, two of whom had a family history of the condition. In collaboration with colleagues at Kings College London, they carried out Next Generation Sequencing (a new technique which can rapidly sequence all the genes in the human genome) on these patients to identify any genetic patterns that could provide clues about the disease. All eight patients had a mutation in the GATA2 gene.

Consultant geneticist, Dr Sahar Mansour, who led the study with Professors Steve Jeffery and Peter Mortimer, said: “Emberger syndrome affects only a handful of people in the UK. However, little is known about the development of both the lymphatic system or leukaemia This gene obviously has a crucial role in both and is an important piece of the jigsaw puzzle. It may lead to a better understanding of why these problems develop and eventually target treatment for both.”

The identification of a mutation in GATA2 adds to the increasing number of genes responsible for causing Primary Lymphoedema. It is the fourth gene to be associated with the condition to be identified at St George’s, which runs the UK’s only specialist clinic for primary lymphoedema.

Professor Mortimer who runs this specialist clinic said: “The genetic causes of lymphoedema are important developments in the understanding of both cause and mechanism for lymphatic disorders which are a neglected area of clinical practice. Gene testing is already changing the means by which lymphoedema is categorised and diagnosed. In the future it will lead to treatment through drugs acting on molecular targets.”